When replying to their service estimate, I too declined the polish.
I cannot determine if the original pins are titanium, but I would think it would be problematic to have dissimilar metals touching, which would lead to galvanic corrosion. I suspect the spring in each link pin release button is steel so maybe this is not a concern between stainless and titanium. I do intend to use this watch as my boating watch so it will get plenty of access to electrolytes in salt water.